The present invention relates to medical devices and more specifically to devices for immobilizing or massaging body limbs, for example, in cases of edema, vein disorders such as chronic venous insufficiency (c.v.i.), varicose veins (v.v), varicose ulcers (v.u.) and others; prevention of deep vein thrombosis; and bone fractures.
In the following description and claims the terms xe2x80x9csleevexe2x80x9d and xe2x80x9ccellxe2x80x9d mean:
Sleevexe2x80x94a hollow cylinder formed of a flexible material into the lumen of which a body limb, e.g. an arm, leg or foot, may be inserted.
Cellxe2x80x94A section of a massaging sleeve which may be inflated or deflated independently of the remainder of the sleeve.
In the condition known as edema, interstitial fluid is inadequately drained by the lymphatics. This causes an accumulation of fluid in the affected tissues leading to painful swelling. When this occurs in a body limb, beneficial results are obtained by massaging the limb in such a way as to force the fluid towards the proximal end of the limb and into the trunk of the body. A number of apparatuses have been devised for this purpose, for example, as disclosed in U.S. Pat. Nos. 5,117,812, 5,007,411, 5,025,781 and 5,591,200. In these apparatuses the limb to be treated is inserted into a massaging sleeve having a plurality of essentially circumferential cells along its length. Each cell is capable of being individually inflated by forcing a fluid into the interior of the cell in order to apply pressure to the limb segment contained within the cell. Each cell is made to undergo cycles of inflation and deflation in order to apply intermittent pressure on the limb segment which it encloses thus achieving a massaging effect on the limb. The inflation-deflation cycles of the different cells in the sleeve are typically staggered so as to generate peristaltic contractions of the sleeve, thus moving fluids inside the limb towards the trunk. In addition to being of benefit in cases of edema, these devices are also useful in the treatment of c.v.i., v.v., v.u. and the prevention of deep vein thrombosis.
In prior art devices, each cell in the sleeve, when deflated, forms essentially a circumferential band around the limb, the circumference of which is selected to correspond to the circumference of the limb segment contained within the cell. Upon inflation, the cell assumes essentially a toroidal shape. In this case, a decrease in the inner circumference of a cell upon inflation is accompanied by an essentially identical increase in the outer circumference of the cell. For example, in order to obtain a 36% decrease in the inner circumference of a cell upon inflation, the outer circumference of the inflated cell must be 36% larger than the original circumference of the limb segment contained therein. The fractional decrease in the inner circumference of the cell corresponds to the amount of pressure applied by the inflated cell to the limb segment contained therein. Thus, in order to obtain useful levels of pressure using prior art devices, the sleeve is of necessity very bulky, stiff and uncomfortable in use and relatively large and powerful compression pumps are required. Prior art devices therefore require the individual to be immobilized during treatment for prolonged periods of time.
It is therefore the object of the present invention to provide a limb massaging device in which the aforementioned disadvantages of the prior art devices are substantially reduced or eliminated.
In accordance with a first aspect of the present invention there is provided a device for applying pressure to a body limb, comprising a sleeve containing a plurality of individually inflatable cells, each cell being subdivided into two or more longitudinally extending confluent compartments which are inflated and deflated essentially simultaneously.
The device according to the invention may, for example, be used to immobilize a fractured bone in a limb by inserting the limb into the sleeve and inflating all the cells thereof so as to render the sleeve rigid and inflexible for the duration of the treatment.
By one mode the invention provides a device for applying pressure to one or more limbs of the body comprising:
(a) a massaging sleeve containing a plurality of individually inflatable cells, each cell being subdivided into two or more longitudinally extending confluent compartments which are inflated and deflated essentially simultaneously;
(b) means for the separate and intermittent inflation of any one of said plurality of inflatable cells; and
(c) control means for determining the temporo-spatial regime of cell inflation.
Typically, and by way of a non-limiting example, a temporo-spatial regime of cell inflation is selected which generates peristaltic contractions of the sleeve. For example, with a sleeve containing 5 cells numbered consecutively from the distal to the proximal end of the limb, cell 1 would first be inflated, followed by cell 2. Cell 1 would then be deflated and cell 3 inflated. Next, cell 2 is deflated as cell 4 is inflated, and then cell 3 is deflated and cell 5 inflated. Finally, cell 4 and then cell 5 are deflated and the cycle begins again. Other temporo-spatial regimes of cell inflation are also contemplated within the scope of the invention.
In accordance with a third aspect of the present invention there is provided a method of massaging a limb of the body of an individual comprising: inserting the limb to be treated into a massaging sleeve of the kind specified and inflating the cells of the sleeve according to a predetermined temporo-spatial regime.
The device according to the invention is applied for example, in cases of edema, c.v.i., v.v., v.u. or preventing deep vein thrombosis.
As will become evident through the description below, subdividing the cells of the sleeve into compartments according to the present invention yields several advantages over prior art devices. Since the diameter of the inflated sleeve is not substantially larger than the diameter of the treated limb, the sleeve may be worn under clothing and is thus concealed during use. Moreover, the sleeve remains flexible and comfortable during use so that the individual need not be immobilized during treatment. Furthermore, the volume of the inflated cells in the present invention is substantially less than in prior art devices, so that a much smaller compressor need be used for inflating the cells. This in turn allows the controlling unit to be substantially lighter than is required for prior art devices. These features allow the individual to be completely ambulatory during treatment.
While in the description given below, the cells in the sleeve are aligned to form an elastic cylinder, the invention is not bound by this constraint and other types of sleeves are contemplated within the scope of the invention. For example, the sleeve may initially be a pad which is wrapped around the limb into an essentially cylindrical shape and then fastened in this configuration by various means.
In operation, a cell is inflated by forcing a fluid into the interior of the cell between the inner and outer shells. While in the description given below a deflated cell forms an essentially circumferential band around the limb, and the fluid used to inflate the cell is air, the invention is not bound by these constraints, and other cell shapes and fluids are contemplated within the scope of the invention.